Fuel delivering device



`Fam. 5, 1932.

' F. HUBER 1,839,878

FUEL DELIVERING DEVICE Filed Nov. 4, 1930 I EN Patented Jan. 5, 1932UNITED STATES PATENT OFFICE FRITZ HUBER, 0F MANNHEIM, GERMANY, ASSIGNGRT0 HEINRICH LANZ AKTIEN- GESELLSCHAFT', 0F MANNHEIM, GERMANY FUELDELIVERING DEVICE Application filed November 4, 1930, Serial No.

The present invention relates to a device for delivering differentliquids by means of a single pump and pressurefpiping with only onepressure valve, the device being particularly adapted to serve as fuelinjecting appliance for heavy oil engines.

Devices for supplying internal combustion engines with two or moreliquid fuels or other liquids in mixed'condition are known already, andthe usual kinds of such devices comprise as a rule one pump piston, apressure valve, a pressure piping, and a nozzle, while the suctionpipings for the various liquids open directly into the suction space ofthe pump. These devices suffer from the drawback that, if the pump hasbeen working for instance with heavy oil,'the entire pump chamber isfilled with heavy oil up to the injection valve and, if during startinga change is to be made to light oil, considerable time is required untilthe heavy oil has been removed from the pum chamber. Furthermore, ifbenzine is use as light oil, the pump piston will work withoutlubrication while delivering the benzine, and similar difculties arisewhen one of the liquids is water which is often added to the heavy fuel.

The invention eliminates these drawbacks by providing means which reducethe amount of heavy oil reaching the nozzle during the alternatedelivery of heavy and light oils and the change from heavy to'light oilto a minimum and which prevent benzine, if used as light oil, fromentering the pump cylinder which thus remains lled with the Wellubricating heavy oil even if benzine is delivered.

According to the invention, these aims are y attained by disposing oneof the suction valves for the different liquids more closely to thestroke space than the other and both in spaced relation to one another.

Another feature of the invention is that the farther removed suctionvalve is arranged in a casing containing also the pressure valve, anarrangement which, for instance in starting devices for heavy oilengines, a'ords the advantaoe that the connection for the light oilpiplng and the pressure valve may be positioned 1n the immedi- 493,289,and in Germany November 22, 1929.

ate neighborhood of the nozzle so that only a minimum of heavy oil isinjected when changing from heavy to light oil.

Still another feature of the invention is that the suction valve opensmore easily for one liquid than for the other, owing to variations inthe spring load of the suction valves or to different arrangement of thetanks for the liquid as to height. Something similar has been proposedalready, but these proposals refer to devices, in which just as manypressure pipingsas suction pipings are required.

Devices for supplying different kinds of fuels to internal combustionengines, in which at a change from heavy to light oil the former pressesthe latter in front of it and into the nozzle, are known which have onlyone fuel pump. However, the suction pipingsfor the various fuels opendirectly into -the pump cylinder so that, if benzine is emplo ed, thepiston will come in touch with it. oreover, the known devices of thisclass require double pressure pipings and double nozzles.

By way of example the invention is illustrated in the accompanyingdrawing in connection with the cylinder head of a hot bulb engine.

Referring to the drawing, a is the fuel pump with the piston b driven bythe eccentric c. When the engine stops, the piston b may be advanced bythe lever CZ' and returned in the known manner by a spring e. From thepump a fuel is supplied to the nozzle f by means of the pipes g and g1.In the immediate neighborhood of the stroke space of the pump thesuction valve 71, for heavy fuel is provided. Between the pipes g and g1a valve casing 21 is disposed' for the reception of the suction valve kfor light fuel and of the pressure valve Z for light and heavy oils. mis the suction piping for the light fuel and can be shut 0H by the cockn. In order to cause the valve to open more easily than the valve L,either the spring closing the valve 7c has less tension than the springclosing the valve z, or the light oil tank is positioned on a higherlevel than the heavy oil tank.

The device functions as follows:

During normal operation with heavy oil the cock n is closed, and thepump sucks up fuel from the 'heavy oil piping through the valve 71, andpresses the oil through the pipe g1 towards the nozzle. When the engineis stopped, the pump a, the pipings g, g1 and the casing z' will befilled with heavy oil. If the engine is to be started with light oil,the cock n 1s opened, and the pump a will then suck up fuel from thepipe m. As the pump as well as the piping g are filled with heavy oil,the aspirated light oil will not reach the stroke space of the pump aand the heavy oil in the stroke space of the pump a and in the piping gwillv not be pressed into the nozzle. The casing z' may be made verysmall and the cross sections of the piping g1 and the nozzle body keptquite narrow so that a few motions of the lever d will suice to removethe heavy oil from the nozzle f and supply the latter with light oil.The piston b does not come into contact with the light oil but merelywith the heavy oil which is superior to light oil in lubricatingquality.

Instead of placing the light oil tank on a higher level than the heavyoil tank or loading the suction valve c with a lighter spring than theheavy oil valve h, the heavy oil piping may be provided with a cockadapted to be closed during light oil operation, though the constructiondescribed is preferred for the reason that it effectively preventsirregularities due tonegligence of the attendants who might forget toclose the cock in the heavy oil piping.

The casing may be structurally united with the nozzle body or with thebody of the pump, in which case provision should be made to retain thepipe g between the stroke space of the pump and-the pressure valve, thepipe ascending preferably from h to Z.

1. A device of the type described comprising a pump, two inlet portsthereto controlled by suction valves and located in spaced relationshipone to the other and at ldifferent distances from the pump, a singleoutlet port therefrom controlled by a pressure valve, and means forselectively causing the pump to pump a fluid from either one of the two.inlet ports and discharge the same through the singleoutlet port.

2. 'A device according to claim 1 in which the inlet port nearest to thepump is connected with a source of supply of a heavy fuel oil and themore remotely located inlet port is connected with a source of supply ofa light fuel oil.

3. A device according to claim 1 in which the two inlet ports areseparated from each other by a vertically disposed pipe serving both toconnect one inlet port with the outlet port and the other inlet portwith the/ pump.

4. A device according to claim 1 in which the suction valve controllingthe more remotely located of the two inlet valves is more easilyresponsive to the action of the 'pump than the suction valve controllingthe inlet port located closer thereto.

5. A device according to claim 1 in which the inlet port nearest to thepump is connected with a sou-rce of supply of a heavy fuel signature.

FRITZ HUBER.

